dconf: revert: dconf: Provide dconf (#7215)

Providing dconf via hm in this manner provided to be problematic for 
user with systems that were already providing dconf (like ubunut).

Revert ff73544e4a

modules/misc/dconf.nix

@@ -33,7 +33,8 @@ in
 
   options = {
     dconf = {
-      enable = lib.mkEnableOption "dconf" // {
+      enable = lib.mkOption {
+        type = types.bool;
         # While technically dconf on darwin could work, our activation step
         # requires dbus, which only *lightly* supports Darwin in general, and
         # not at all in the way it's packaged in nixpkgs. Because of this, we
@@ -42,6 +43,13 @@ in
         # re-enabled, unclear whether there's actual value in it though.
         default = !pkgs.stdenv.hostPlatform.isDarwin;
         visible = false;
+        description = ''
+          Whether to enable dconf settings.Add commentMore actions
+          Note, if you use NixOS then you must add
+          `programs.dconf.enable = true`
+          to your system configuration. Otherwise you will see a systemd error
+          message when your configuration is activated.
+        '';
       };
 
       settings = lib.mkOption {
@@ -76,79 +84,70 @@ in
     };
   };
 
-  config = lib.mkMerge [
-    (lib.mkIf cfg.enable {
-      home.packages = [ pkgs.dconf ];
-      dbus.packages = [ pkgs.dconf ];
-      home.sessionVariablesExtra = ''
-        export GIO_EXTRA_MODULES="${pkgs.dconf.lib}/lib/gio/modules''${GIO_EXTRA_MODULES:+:}$GIO_EXTRA_MODULES"
-      '';
-    })
-    (lib.mkIf (cfg.enable && cfg.settings != { }) {
-      # Make sure the dconf directory exists.
-      xdg.configFile."dconf/.keep".source = builtins.toFile "keep" "";
+  config = lib.mkIf (cfg.enable && cfg.settings != { }) {
+    # Make sure the dconf directory exists.
+    xdg.configFile."dconf/.keep".source = builtins.toFile "keep" "";
 
-      home.extraBuilderCommands = ''
-        mkdir -p $out/state/
-        ln -s ${stateDconfKeys} $out/state/${stateDconfKeys.name}
-      '';
+    home.extraBuilderCommands = ''
+      mkdir -p $out/state/
+      ln -s ${stateDconfKeys} $out/state/${stateDconfKeys.name}
+    '';
 
-      home.activation.dconfSettings = lib.hm.dag.entryAfter [ "installPackages" ] (
-        let
-          iniFile = pkgs.writeText "hm-dconf.ini" (toDconfIni cfg.settings);
+    home.activation.dconfSettings = lib.hm.dag.entryAfter [ "installPackages" ] (
+      let
+        iniFile = pkgs.writeText "hm-dconf.ini" (toDconfIni cfg.settings);
 
-          statePath = "state/${stateDconfKeys.name}";
+        statePath = "state/${stateDconfKeys.name}";
 
-          cleanup = pkgs.writeShellScript "dconf-cleanup" ''
-            set -euo pipefail
+        cleanup = pkgs.writeShellScript "dconf-cleanup" ''
+          set -euo pipefail
 
-            ${config.lib.bash.initHomeManagerLib}
+          ${config.lib.bash.initHomeManagerLib}
 
-            PATH=${
-              lib.makeBinPath [
-                pkgs.dconf
-                pkgs.jq
-              ]
-            }''${PATH:+:}$PATH
+          PATH=${
+            lib.makeBinPath [
+              pkgs.dconf
+              pkgs.jq
+            ]
+          }''${PATH:+:}$PATH
 
-            oldState="$1"
-            newState="$2"
+          oldState="$1"
+          newState="$2"
 
-            # Can't do cleanup if we don't know the old state.
-            if [[ ! -f $oldState ]]; then
-              exit 0
-            fi
-
-            # Reset all keys that are present in the old generation but not the new
-            # one.
-            jq -r -n \
-                --slurpfile old "$oldState" \
-                --slurpfile new "$newState" \
-                '($old[] - $new[])[]' \
-              | while read -r key; do
-                  verboseEcho "Resetting dconf key \"$key\""
-                  run $DCONF_DBUS_RUN_SESSION dconf reset "$key"
-                done
-          '';
-        in
-        ''
-          if [[ -v DBUS_SESSION_BUS_ADDRESS ]]; then
-            export DCONF_DBUS_RUN_SESSION=""
-          else
-            export DCONF_DBUS_RUN_SESSION="${pkgs.dbus}/bin/dbus-run-session --dbus-daemon=${pkgs.dbus}/bin/dbus-daemon"
+          # Can't do cleanup if we don't know the old state.
+          if [[ ! -f $oldState ]]; then
+            exit 0
           fi
 
-          if [[ -v oldGenPath ]]; then
-            ${cleanup} \
-              "$oldGenPath/${statePath}" \
-              "$newGenPath/${statePath}"
-          fi
+          # Reset all keys that are present in the old generation but not the new
+          # one.
+          jq -r -n \
+              --slurpfile old "$oldState" \
+              --slurpfile new "$newState" \
+              '($old[] - $new[])[]' \
+            | while read -r key; do
+                verboseEcho "Resetting dconf key \"$key\""
+                run $DCONF_DBUS_RUN_SESSION dconf reset "$key"
+              done
+        '';
+      in
+      ''
+        if [[ -v DBUS_SESSION_BUS_ADDRESS ]]; then
+          export DCONF_DBUS_RUN_SESSION=""
+        else
+          export DCONF_DBUS_RUN_SESSION="${pkgs.dbus}/bin/dbus-run-session --dbus-daemon=${pkgs.dbus}/bin/dbus-daemon"
+        fi
 
-          run $DCONF_DBUS_RUN_SESSION ${pkgs.dconf}/bin/dconf load / < ${iniFile}
+        if [[ -v oldGenPath ]]; then
+          ${cleanup} \
+            "$oldGenPath/${statePath}" \
+            "$newGenPath/${statePath}"
+        fi
 
-          unset DCONF_DBUS_RUN_SESSION
-        ''
-      );
-    })
-  ];
+        run $DCONF_DBUS_RUN_SESSION ${pkgs.dconf}/bin/dconf load / < ${iniFile}
+
+        unset DCONF_DBUS_RUN_SESSION
+      ''
+    );
+  };
 }

tests/modules/home-environment/session-variables.nix

@@ -17,7 +17,6 @@ let
     export XDG_DATA_HOME="/home/hm-user/.local/share"
     export XDG_STATE_HOME="/home/hm-user/.local/state"
 
-    export GIO_EXTRA_MODULES="${pkgs.dconf}/lib/gio/modules''${GIO_EXTRA_MODULES:+:}$GIO_EXTRA_MODULES"
   '';
 
   darwinExpected = ''